1. Field of the Invention
This present invention relates to a back lighting module, and more specifically to a frame member of a back lighting module.
2. The Related Art
A liquid crystal display (LCD) is used extensively in personal computers, mobile phones, PDAs, etc, because of the feature of light weight, small dimension and low power consumption. The LCD has a back lighting module. The back lighting module includes a frame member and an optical element mounted in the frame member. Generally, the frame member includes a housing and a plastic frame. The housing may be made by punching a metal sheet. The housing and the plastic frame are integrally bonded to each other in injection molding manner for reducing the size and enhancing the intensity of the frame member.
FIG. 1 is a schematic view showing structure of the frame member of the back lighting module. The frame member includes a housing 30 and a plastic frame 40 combined with the housing 30. The housing 30 defines a basic plate 31 and a lateral plate 32 extending upwards from an edge of the basic plate 31. The lateral plate 32 has a through hole 33. The plastic frame 40 is integrally bonded to the housing 30 by injection molding. However, in process of the plastic frame 40 molded with the housing 30, the holding time of the melting plastic flowing through the through hole 33 is longer than that of other places. As a result, the fluidity of the melting plastic comes down so as to affect the quality of the plastic frame 40 combined with the housing 30.